Title :
VTH-hopping scheme to reduce subthreshold leakage for low-power processors
Author :
Nose, Koichi ; Hirabayashi, Masayuki ; Kawaguchi, Hiroshi ; Lee, Seongsoo ; Sakurai, Takayasu
Author_Institution :
Inst. of Ind. Sci., Univ. of Tokyo, Japan
fDate :
3/1/2002 12:00:00 AM
Abstract :
In order to suppress the power consumption in low-voltage processors, a threshold voltage hopping (VTH-hopping) scheme is proposed where the threshold voltage is dynamically controlled through software depending on a workload. VTH-hopping is shown to reduce the power to 18 % of the fixed low-threshold voltage circuits in 0.5-V supply voltage regime for multimedia applications. A positive back-gate bias scheme with VTH-hopping is presented for the high-performance and low-voltage processors. In order to verify the effectiveness of VTH-hopping, a small-scale RISC processor with VTH-hopping capability and the positive back-gate bias scheme is fabricated in a 0.6-μm CMOS technology. MPEG4 encoding is simulated based on the measured data. The result shows that 86% power saving can be achieved by using VTH-hopping compared with the fixed positive back-gate bias scheme
Keywords :
CMOS digital integrated circuits; integrated circuit design; leakage currents; low-power electronics; microprocessor chips; multimedia computing; reduced instruction set computing; video coding; 0.5 V; 0.5-V supply voltage regime; 0.6 micron; CMOS technology; MPEG-4 video coding; VTH-hopping scheme; VLSI design; hardware-software cooperation; low-power processors; low-threshold voltage circuits; multimedia applications; positive back-gate bias scheme; power consumption suppression; power saving; small-scale RISC processor; subthreshold leakage reduction; threshold voltage dynamic control; threshold voltage hopping scheme; Application software; CMOS process; CMOS technology; Circuits; Encoding; Energy consumption; MPEG 4 Standard; Reduced instruction set computing; Threshold voltage; Voltage control;
Journal_Title :
Solid-State Circuits, IEEE Journal of
